Enhancement of superhorizon scale inflationary curvature perturbations

Abstract

We show that there exists a simple mechanism which can enhance the amplitude of curvature perturbations on superhorizon scales during inflation, relative to their amplitude at horizon crossing. The enhancement may occur even in a single-field inflaton model, and occurs if the quantity $a\dot{\varphi }/H$ becomes sufficiently small, as compared to its value at horizon crossing, for some time interval during inflation. We give a criterion for this enhancement in general single-field inflation models.

5 pages RevTeX file with 2 figures incorporated v2:Contains important O(k^2) correction

Cited by in corpus (175)

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